1. Field of the Invention
The present invention is related to a method, system and program for network environment notifying, which are used to investigate a network environment of a user so as to notify the investigated network environment when a communication application program such as a network telephone and a TV telephone is used on a network.
2. Description of the Related Art
Very recently, while networks such as the Internet are positively popularized, networks are utilized in fields other than electronic mails and WWW (World Wide Web) browsing.
On the other hand, in IP networks using IP (Internet Protocol), which is typically known as the Internet, there is such a problem that IP addresses are exhausted in accordance with the presently popularized IPv4. Also, local networks are constructed in these IP networks. That is, in such a local network, private IP addresses have been allocated to the respective terminals by employing such an address translation function as NAT (Network Address Translation) and IP Masquerade, in which a single global IP address is commonly used by a plurality of terminals. Very recently, dial-up routers equipped with functions as NAT and IP Masquerade have been marketed in low cost, and thus, have been popularized. Also, in a certain network in which a certain cable TV station may provide services, while global IP addresses are not opened with respect to user terminals, only such an environment of private IP addresses based upon NAT and IP Masquerade is provided.
Under such a circumstance, for instance, when either a network telephone or a TV telephone using the H.323 protocol is used, since the IP Masquerade is utilized, there is a problem that a communication cannot be established by terminals to which private IP addresses have been allocated.
Conventionally, application programs (application software) capable of providing network telephone functions and TV telephone functions on terminals by personal computers (will be referred to as “PCs” hereinafter) have been originally designed for such a case that PCs under use may acquire global IP addresses and are connected to the Internet, or such a case that PCs under use establish communications within one private network. Therefore, such PCs having private IP addresses operated under IP Masquerade environment cannot communicate with terminals of counter parties via the Internet. Under such an IP Masquerade environment, users make a large number of complaints as well as a great number of interrogations such as “application programs cannot be used” with respect to support stations of these application programs providers, which may increase supporting cost of these application programs providers.
Even when such terminals are employed to which private IP addresses have been allocated under IP Masquerade, these terminals may use network telephones and TV telephones, which utilize the H.323 protocol, in accordance with conventional techniques where exclusively-dedicated gateway apparatus are provided. For instance, Japanese Laid-open Patent Application No. 2001-156852 discloses the network address translating apparatus. That is, this network address translating apparatus is comprised of the call control translating unit and the voice converting unit in addition to the address translating unit for transferring the address requests among the gate keepers of the plural IP networks so as to acquire the address information. This call control translating unit transfers the call setting requests among the gate keepers, and also, sets the translation information by referring to the address information, and then, produces the voice port corresponding thereto. The voice converting unit transfers the voice signal by using the voice port produced with reference to the translation information. With employment of such an arrangement, both the telephone calling and the call reception can be available between the terminals having the private IP addresses, which cannot be accessed outside the IP networks, and the terminals to which either the global IP addresses or the private IP addresses of other networks have been allocated.